* ggc-common.c (ggc_mark_rtx_children_1): Rename from...

        (ggc_mark_rtx_children): New.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@52864 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 38 insertions, 0 deletions

diff --git a/gcc/ggc-common.c b/gcc/ggc-common.c
index 6a6b69b3dd8..a90a01fb51a 100644
--- a/gcc/ggc-common.c
+++ b/gcc/ggc-common.c
@@ -38,6 +38,7 @@ static ggc_statistics *ggc_stats;
 /* Trees that have been marked, but whose children still need marking.  */
 varray_type ggc_pending_trees;
 
+static void ggc_mark_rtx_children_1 PARAMS ((rtx));
 static void ggc_mark_rtx_ptr PARAMS ((void *));
 static void ggc_mark_tree_ptr PARAMS ((void *));
 static void ggc_mark_rtx_varray_ptr PARAMS ((void *));
@@ -272,6 +273,43 @@ void
 ggc_mark_rtx_children (r)
      rtx r;
 {
+  rtx i, last;
+
+  /* Special case the instruction chain.  This is a data structure whose
+     chain length is potentially unbounded, and which contain references
+     within the chain (e.g. label_ref and insn_list).  If do nothing here,
+     we risk blowing the stack recursing through a long chain of insns.
+
+     Combat this by marking all of the instructions in the chain before
+     marking the contents of those instructions.  */
+
+  switch (GET_CODE (r))
+    {
+    case INSN:
+    case JUMP_INSN:
+    case CALL_INSN:
+    case NOTE:
+    case CODE_LABEL:
+    case BARRIER:
+      for (i = NEXT_INSN (r); ; i = NEXT_INSN (i))
+	if (! ggc_test_and_set_mark (i))
+	  break;
+      last = i;
+
+      for (i = NEXT_INSN (r); i != last; i = NEXT_INSN (i))
+	ggc_mark_rtx_children_1 (i);
+
+    default:
+      break;
+    }
+
+  ggc_mark_rtx_children_1 (r);
+}
+
+static void
+ggc_mark_rtx_children_1 (r)
+     rtx r;
+{
   const char *fmt;
   int i;
   rtx next_rtx;